Thibault Carteret1, Mathilde Merle1, Gregory Maclair1, Baudouin denis de Senneville1, Chrit Moonen1, Bruno Quesson1
1CNRS/Universit Bordeaux 2, Laboratory for
Molecular and Functional Imaging, Bordeaux, France
MRI-thermometry on mobile organs requires minimal out-out-plane motion to efficiently monitor the temperature evolution. Local organ displacements were computed in orthogonal images acquired during free breathing and a Principal Component Analysis of the calculated motion field vectors was performed to determine the principal axis of motion and to correct the slice angulations in 3D. The resulting precision of MRI-thermometry in vivo on humans was significantly improved in the liver and kidney. This method only requires few minutes extra acquisition time and provides in addition the target trajectory in 3D, which can be included in the planning of the therapy.